1640965 has 8 divisors (see below), whose sum is σ = 2037240. Its totient is φ = 1267392.

The previous prime is 1640953. The next prime is 1640971. The reversal of 1640965 is 5690461.

It can be written as a sum of positive squares in 4 ways, for example, as 588289 + 1052676 = 767^2 + 1026^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1640965 - 2¹⁵ = 1608197 is a prime.

It is a super-2 number, since 2×1640965² = 5385532262450, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5514 + ... + 5803.

It is an arithmetic number, because the mean of its divisors is an integer number (254655).

2^1640965 is an apocalyptic number.

It is an amenable number.

1640965 is a deficient number, since it is larger than the sum of its proper divisors (396275).

1640965 is a wasteful number, since it uses less digits than its factorization.

1640965 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11351.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 1640965 is about 1281.0015612793. The cubic root of 1640965 is about 117.9504963278.

The spelling of 1640965 in words is "one million, six hundred forty thousand, nine hundred sixty-five".